Investigation of deferiprone binding to different essential metal ions using microscale thermophoresis and electrospray ionization mass spectrometry

摘要

AbstractIn this study, the microscale thermophoresis (MST) method was applied to investigate the interaction of deferiprone with Fe3+, Cu2+, Zn2+, Co2+, Ni2+, Mn2+, Mg2+, and Ca2+. Experiments were performed on a MST (Monolith NT.115 LabelFree?) system. Pretest scanning indicated good fluorescence intensity of deferiprone allowing the use of label-free MST experiments. Different concentrations of the intended metal ions in the range of 0.048 to 100.0μM were titrated against 100μM fixed concentration of deferiprone dissolved in 0.1M Tris buffer pH7.4. MST measurements were performed in standard capillaries at 50% excitation power and 20% MST power. The results indicated significant interactions of deferiprone with Fe3+, Cu2+, Zn2+, Co2+, and Ni2+. The data fitted to the Hill model with Hill coefficients of 1.8, 1.5, 3.2, 1.6, and 1.5 for Fe3+, Cu2+, Zn2+, Ni2+, Co2+, respectively, thus indicating more than 1:1 stoichiometry. EC50 values for the binding of deferiprone to Fe3+, Cu2+, Zn2+, Co2+, and Ni2+were calculated to be 20.6±3.34, 38.1±3.3